The discovery of hepatitis B surface antigen (HBsAg, Australian antigen, or hepatitis-associated antigen) represented a major scientific breakthrough in the characterization and treatment of hepatitis B virus (HBV). The development of a HBV vaccine using HBsAg protected against infection by HBV in most cases but not all. In the early 1970's a second antibody, distinct from anti-HBs, was discovered in response to HBV infection. This second antibody, anti-HBc (anti-core), is directed against the hepatitis B core antigen (HBcAg), located on the internal component of the Dane particle, the intact hepatitis B virus and the core antigen particles found in the liver during chronic infection. However, no material suitable for use as a vaccine has been developed using the inner component, HBcAg. The present invention discloses the preparation of a vaccine against HBV using purified hepatitis B core antigen. This vaccine has been tested in chimpanzees, protecting them against HBV infection. All hepatitis B vaccines shown to be effective in chimpanzees have also been effective in humans.